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<html lang="zh-CN">

<head>
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    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=no">
    <meta name="author" content="何毓堂">
    <title></title>
    <link rel="stylesheet" type="" href="">
    <style>
        div {
            border: 1px solid black;
            height: 300px;
        }

        ul {
            width: 1200px;  
            list-style: none;
            display: flex;
            flex-wrap: wrap;
            justify-content: space-around;
            margin: 0 auto;
            padding: 0;
        }
        header{
            width: 100%;
            height: 60px;
            background-color: #aaa;
        }
        nav {
            width: 1200px;
            height: 60px;
            line-height: 60px;
            background-color: black;
            display: flex;
            flex-wrap: wrap;
            justify-content: space-around;
            margin: 0 auto;
            color: white;
        }

        span {
            width: 300px;
            margin: 0;
            padding: 0;
            text-align: center;
        }
        li{
            width: 100px;
            text-align: center;
            margin: 0 auto;
            border: 1px solid #ccc;
            background-color: #FFFFFF;
            opacity: 0;
        }
        a{
            color: #aaa;
            text-decoration: none;           
        }
    </style>
</head>

<body>
    <div>
        <header>
            <nav>
            <span><a href="">公司简介</a></span>
            <span><a href="">产品介绍</a></span>
            <span><a href="">联系我们</a></span>
            <span><a href="">人才招聘</a></span>
        </nav>
        </header>
        <ul>
            <li>
                <p><a href="">概况介绍</a></p>
                <p><a href="">发展历史</a></p>
                <p><a href="">公司实力</a></p>
            </li>
            <li>
                <p><a href="">软件研发</a></p>
                <p><a href="">软件教育</a></p>
                <p><a href="">天使投资</a></p>

            </li>
            <li>
                <p><a href="">公司地址</a></p>
                <p><a href="">联系方式</a></p>
                <p> <a href="">投资加盟</a> </p>
            </li>
            <li>
                <p><a href="">Java招聘</a></p>
                <p><a href="">HTML5招聘</a></p>
                <p><a href="">PHP招聘</a></p>
            </li>
        </ul>
    </div>

    <script src="./jquery.js"></script>
</body>

</html>              
<script>
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    $("span").mouseover(function(){
    $("a").eq($(this).index()).css("color","gold").css("text-decoration","underline");
    $('li').eq($(this).index()).css('opacity','1').siblings().css('opacity','0')
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    $(this).css("color","gold").css("text-decoration","underline")
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  });
  $("span").mouseout(function(){
    $("a").eq($(this).index()).css("color","#aaa").css("text-decoration","none");
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</script>
